diff --git a/test/built-ins/Array/prototype/lastIndexOf/length-near-integer-limit.js b/test/built-ins/Array/prototype/lastIndexOf/length-near-integer-limit.js new file mode 100644 index 0000000000..93e0538736 --- /dev/null +++ b/test/built-ins/Array/prototype/lastIndexOf/length-near-integer-limit.js @@ -0,0 +1,35 @@ +// Copyright (C) 2020 Alexey Shvayka. All rights reserved. +// This code is governed by the BSD license found in the LICENSE file. + +/*--- +esid: sec-array.prototype.lastindexof +description: > + Elements are found in an array-like object + whose "length" property is near the integer limit. +info: | + Array.prototype.lastIndexOf ( searchElement [ , fromIndex ] ) + + 1. Let O be ? ToObject(this value). + 2. Let len be ? LengthOfArrayLike(O). + [...] + 7. Repeat, while k ≥ 0 + a. Let kPresent be ? HasProperty(O, ! ToString(k)). + b. If kPresent is true, then + i. Let elementK be ? Get(O, ! ToString(k)). + ii. Let same be the result of performing Strict Equality Comparison searchElement === elementK. + iii. If same is true, return k. + [...] +---*/ + +var el = {}; +var elIndex = Number.MAX_SAFE_INTEGER - 3; +var fromIndex = Number.MAX_SAFE_INTEGER - 1; +var arrayLike = { + length: Number.MAX_SAFE_INTEGER, +}; + +arrayLike[elIndex] = el; + +var res = Array.prototype.lastIndexOf.call(arrayLike, el, fromIndex); + +assert.sameValue(res, elIndex);